-.\" $Id: mandoc_char.7,v 1.63 2015/09/02 15:38:35 schwarze Exp $
+.\" $Id: mandoc_char.7,v 1.78 2020/10/31 11:45:16 schwarze Exp $
.\"
.\" Copyright (c) 2003 Jason McIntyre <jmc@openbsd.org>
.\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
-.\" Copyright (c) 2011, 2013, 2015 Ingo Schwarze <schwarze@openbsd.org>
+.\" Copyright (c) 2011,2013,2015,2017-2020 Ingo Schwarze <schwarze@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
-.Dd $Mdocdate: September 2 2015 $
+.Dd $Mdocdate: October 31 2020 $
.Dt MANDOC_CHAR 7
.Os
.Sh NAME
.Pp
The rendering depends on the
.Xr mandoc 1
-output mode; in ASCII output, most characters are completely
-unintelligible.
-For that reason, using any of the special characters documented here,
-except those discussed in the
+output mode; it can be inspected by calling
+.Xr man 1
+on the
+.Nm
+manual page with different
+.Fl T
+arguments.
+In ASCII output, the rendering of some characters may be hard
+to interpret for the reader.
+Many are rendered as descriptive strings like
+.Qq <integral> ,
+.Qq <degree> ,
+or
+.Qq <Gamma> ,
+which may look ugly, and many are replaced by similar ASCII characters.
+In particular, accented characters are usually shown without the accent.
+For that reason, try to avoid using any of the special characters
+documented here except those discussed in the
.Sx DESCRIPTION ,
-is strongly discouraged; they are supported merely for backwards
-compatibility with existing documents.
+unless they are essential for explaining the subject matter at hand,
+for example when documenting complicated mathematical functions.
.Pp
In particular, in English manual pages, do not use special-character
escape sequences to represent national language characters in author
names; instead, provide ASCII transcriptions of the names.
.Ss Dashes and Hyphens
In typography there are different types of dashes of various width:
-the hyphen (-),
-the minus sign (\(mi),
+the hyphen (\(hy),
the en-dash (\(en),
-and the em-dash (\(em).
+the em-dash (\(em),
+and the mathematical minus sign (\(mi).
.Pp
Hyphens are used for adjectives;
to separate the two parts of a compound word;
lorry-driver
.Ed
.Pp
-The mathematical minus sign is used for negative numbers or subtraction.
-It should be written as
-.Sq \e(mi :
-.Bd -unfilled -offset indent
-a = 3 \e(mi 1;
-b = \e(mi2;
-.Ed
-.Pp
The en-dash is used to separate the two elements of a range,
or can be used the same way as an em-dash.
It should be written as
This is not that \e(em rather, this is that.
.Ed
.Pp
-Note:
-hyphens, minus signs, and en-dashes look identical under normal ASCII output.
-Other formats, such as PostScript, render them correctly,
-with differing widths.
+In
+.Xr roff 7
+documents, the minus sign is normally written as
+.Sq \e- .
+In manual pages, some style guides recommend to also use
+.Sq \e-
+if an ASCII 0x2d
+.Dq hyphen-minus
+output glyph that can be copied and pasted is desired in output modes
+supporting it, for example in
+.Fl T Cm utf8
+and
+.Fl T Cm html .
+But currently, no practically relevant manual page formatter requires
+that subtlety, so in manual pages, it is sufficient to write plain
+.Sq -
+to represent hyphen, minus, and hyphen-minus.
+.Pp
+If a word on a text input line contains a hyphen, a formatter may decide
+to insert an output line break after the hyphen if that helps filling
+the current output line, but the whole word would overflow the line.
+If it is important that the word is not broken across lines in this
+way, a zero-width space
+.Pq Sq \e&
+can be inserted before or after the hyphen.
+While
+.Xr mandoc 1
+never breaks the output line after hyphens adjacent to a zero-width
+space, after any of the other dash- or hyphen-like characters
+represented by escape sequences, or after hyphens inside words in
+macro arguments, other software may not respect these rules and may
+break the line even in such cases.
+.Pp
+Some
+.Xr roff 7
+implementations contains dictionaries allowing to break the line
+at syllable boundaries even inside words that contain no hyphens.
+Such automatic hyphenation is not supported by
+.Xr mandoc 1 ,
+which only breaks the line at whitespace, and inside words only
+after existing hyphens.
.Ss Spaces
To separate words in normal text, for indenting and alignment
in literal context, and when none of the following special cases apply,
.Ss Accents
In output modes supporting such special output characters, for example
.Fl T Cm pdf ,
+and sometimes less consistently in
+.Fl T Cm utf8 ,
some
.Xr roff 7
formatters convert the following ASCII input characters to the
.It \(ga Ta U+2018 Ta left single quotation mark
.It \(aq Ta U+2019 Ta right single quotation mark
.It \(ti Ta U+02DC Ta small tilde
+.It \(ha Ta U+02C6 Ta modifier letter circumflex
.El
.Pp
In prose, this automatic substitution is often desirable;
.It \e(ga Ta U+0060 Ta grave accent
.It \e(aq Ta U+0027 Ta apostrophe
.It \e(ti Ta U+007E Ta tilde
+.It \e(ha Ta U+005E Ta circumflex accent
.El
.Ss Periods
The period
.Xr roff 7
manual.
.Pp
-Spacing:
+Spaces, non-breaking unless stated otherwise:
.Bl -column "Input" "Description" -offset indent -compact
.It Em Input Ta Em Description
-.It Sq \e\ \& Ta unpaddable non-breaking space
-.It \e\(ti Ta paddable non-breaking space
-.It \e0 Ta unpaddable, breaking digit-width space
+.It Sq \e\ \& Ta unpaddable space
+.It \e\(ti Ta paddable space
+.It \e0 Ta digit-width space
.It \e| Ta one-sixth \e(em narrow space, zero width in nroff mode
.It \e^ Ta one-twelfth \e(em half-narrow space, zero width in nroff
.It \e& Ta zero-width space
+.It \e) Ta zero-width space transparent to end-of-sentence detection
.It \e% Ta zero-width space allowing hyphenation
+.It \e: Ta zero-width space allowing line break
.El
.Pp
Lines:
.It \e(ba Ta \(ba Ta bar
.It \e(br Ta \(br Ta box rule
.It \e(ul Ta \(ul Ta underscore
+.It \e(ru Ta \(ru Ta underscore (width 0.5m)
.It \e(rn Ta \(rn Ta overline
.It \e(bb Ta \(bb Ta broken bar
.It \e(sl Ta \(sl Ta forward slash
.It \e(sh Ta \(sh Ta hash (pound)
.It \e(CR Ta \(CR Ta carriage return
.It \e(OK Ta \(OK Ta check mark
+.It \e(CL Ta \(CL Ta club suit
+.It \e(SP Ta \(SP Ta spade suit
+.It \e(HE Ta \(HE Ta heart suit
+.It \e(DI Ta \(DI Ta diamond suit
.El
.Pp
Legal symbols:
.It \e(rq Ta \(rq Ta right double-quote
.It \e(oq Ta \(oq Ta left single-quote
.It \e(cq Ta \(cq Ta right single-quote
-.It \e(aq Ta \(aq Ta apostrophe quote (text)
-.It \e(dq Ta \(dq Ta double quote (text)
+.It \e(aq Ta \(aq Ta apostrophe quote (ASCII character)
+.It \e(dq Ta \(dq Ta double quote (ASCII character)
.It \e(Fo Ta \(Fo Ta left guillemet
.It \e(Fc Ta \(Fc Ta right guillemet
.It \e(fo Ta \(fo Ta left single guillemet
.It \e(rC Ta \(rC Ta right brace
.It \e(la Ta \(la Ta left angle
.It \e(ra Ta \(ra Ta right angle
-.It \e(bv Ta \(bv Ta brace extension
+.It \e(bv Ta \(bv Ta brace extension (special font)
.It \e[braceex] Ta \[braceex] Ta brace extension
.It \e[bracketlefttp] Ta \[bracketlefttp] Ta top-left hooked bracket
.It \e[bracketleftbt] Ta \[bracketleftbt] Ta bottom-left hooked bracket
.It \e(uA Ta \(uA Ta up double-arrow
.It \e(dA Ta \(dA Ta down double-arrow
.It \e(vA Ta \(vA Ta up-down double-arrow
+.It \e(an Ta \(an Ta horizontal arrow extension
.El
.Pp
Logical:
.It Em Input Ta Em Rendered Ta Em Description
.It \e(AN Ta \(AN Ta logical and
.It \e(OR Ta \(OR Ta logical or
-.It \e(no Ta \(no Ta logical not
-.It \e[tno] Ta \[tno] Ta logical not (text)
+.It \e[tno] Ta \[tno] Ta logical not (text font)
+.It \e(no Ta \(no Ta logical not (special font)
.It \e(te Ta \(te Ta existential quantifier
.It \e(fa Ta \(fa Ta universal quantifier
.It \e(st Ta \(st Ta such that
Mathematical:
.Bl -column "xxcoproductxx" "Rendered" "Description" -offset indent -compact
.It Em Input Ta Em Rendered Ta Em Description
-.It \e(pl Ta \(pl Ta plus
-.It \e(mi Ta \(mi Ta minus
-.It \e- Ta \- Ta minus (text)
+.It \e- Ta \- Ta minus (text font)
+.It \e(mi Ta \(mi Ta minus (special font)
+.It + Ta + Ta plus (text font)
+.It \e(pl Ta \(pl Ta plus (special font)
.It \e(-+ Ta \(-+ Ta minus-plus
-.It \e(+- Ta \(+- Ta plus-minus
-.It \e[t+-] Ta \[t+-] Ta plus-minus (text)
+.It \e[t+-] Ta \[t+-] Ta plus-minus (text font)
+.It \e(+- Ta \(+- Ta plus-minus (special font)
.It \e(pc Ta \(pc Ta center-dot
-.It \e(mu Ta \(mu Ta multiply
-.It \e[tmu] Ta \[tmu] Ta multiply (text)
+.It \e[tmu] Ta \[tmu] Ta multiply (text font)
+.It \e(mu Ta \(mu Ta multiply (special font)
.It \e(c* Ta \(c* Ta circle-multiply
.It \e(c+ Ta \(c+ Ta circle-plus
-.It \e(di Ta \(di Ta divide
-.It \e[tdi] Ta \[tdi] Ta divide (text)
+.It \e[tdi] Ta \[tdi] Ta divide (text font)
+.It \e(di Ta \(di Ta divide (special font)
.It \e(f/ Ta \(f/ Ta fraction
.It \e(** Ta \(** Ta asterisk
.It \e(<= Ta \(<= Ta less-than-equal
.It \e(Ah Ta \(Ah Ta aleph
.It \e(Im Ta \(Im Ta imaginary
.It \e(Re Ta \(Re Ta real
+.It \e(wp Ta \(wp Ta Weierstrass p
.It \e(pd Ta \(pd Ta partial differential
.It \e(-h Ta \(-h Ta Planck constant over 2\(*p
-.It \e[12] Ta \[12] Ta one-half
-.It \e[14] Ta \[14] Ta one-fourth
-.It \e[34] Ta \[34] Ta three-fourths
+.It \e[hbar] Ta \[hbar] Ta Planck constant over 2\(*p
+.It \e(12 Ta \(12 Ta one-half
+.It \e(14 Ta \(14 Ta one-fourth
+.It \e(34 Ta \(34 Ta three-fourths
+.It \e(18 Ta \(18 Ta one-eighth
+.It \e(38 Ta \(38 Ta three-eighths
+.It \e(58 Ta \(58 Ta five-eighths
+.It \e(78 Ta \(78 Ta seven-eighths
+.It \e(S1 Ta \(S1 Ta superscript 1
+.It \e(S2 Ta \(S2 Ta superscript 2
+.It \e(S3 Ta \(S3 Ta superscript 3
.El
.Pp
Ligatures:
.It \e(ao Ta \(ao Ta ring
.It \e(a\(ti Ta \(a~ Ta tilde
.It \e(ho Ta \(ho Ta ogonek
-.It \e(ha Ta \(ha Ta hat (text)
-.It \e(ti Ta \(ti Ta tilde (text)
+.It \e(ha Ta \(ha Ta hat (ASCII character)
+.It \e(ti Ta \(ti Ta tilde (ASCII character)
.El
.Pp
Accented letters:
.It \e(\(aqI Ta \('I Ta acute I
.It \e(\(aqO Ta \('O Ta acute O
.It \e(\(aqU Ta \('U Ta acute U
+.It \e(\(aqY Ta \('Y Ta acute Y
.It \e(\(aqa Ta \('a Ta acute a
.It \e(\(aqe Ta \('e Ta acute e
.It \e(\(aqi Ta \('i Ta acute i
.It \e(\(aqo Ta \('o Ta acute o
.It \e(\(aqu Ta \('u Ta acute u
+.It \e(\(aqy Ta \('y Ta acute y
.It \e(\(gaA Ta \(`A Ta grave A
.It \e(\(gaE Ta \(`E Ta grave E
.It \e(\(gaI Ta \(`I Ta grave I
.It \e(fm Ta \(fm Ta minute
.It \e(sd Ta \(sd Ta second
.It \e(mc Ta \(mc Ta micro
+.It \e(Of Ta \(Of Ta Spanish female ordinal
+.It \e(Om Ta \(Om Ta Spanish masculine ordinal
.El
.Pp
Greek letters:
and
.Sq \e*[N]
.Pq N-character .
-For details, see the
-.Em Predefined Strings
-subsection of the
-.Xr roff 7
-manual.
.Bl -column "Input" "Rendered" "Description" -offset indent
.It Em Input Ta Em Rendered Ta Em Description
.It \e*(Ba Ta \*(Ba Ta vertical bar
.Xr mandoc 1
also supports the
.Pp
-.Dl \eN\(aq Ns Ar number Ns \(aq
+.Dl \eN\(aq Ns Ar number Ns \(aq and \e[ Ns Cm char Ns Ar number ]
.Pp
-escape sequence, inserting the character
+escape sequences, inserting the character
.Ar number
from the current character set into the output.
Of course, this is inherently non-portable and is already marked
-as deprecated in the Heirloom roff manual.
-For example, do not use \eN\(aq34\(aq, use \e(dq, or even the plain
+as deprecated in the Heirloom roff manual;
+on top of that, the second form is a GNU extension.
+For example, do not use \eN\(aq34\(aq or \e[char34], use \e(dq,
+or even the plain
.Sq \(dq
character where possible.
.Sh COMPATIBILITY
differently between mandoc and groff.
.It
In
-.Fl T Ns Cm html
-and
-.Fl T Ns Cm xhtml ,
+.Fl T Ns Cm html ,
the \e(\(ti=, \e(nb, and \e(nc special characters render differently
between mandoc and groff.
.It
git.ckatri.com / mandoc.git / blobdiff